Method and apparatus for manufacturing rubber articles



Aug- 9, 1932. w. A. GlBBoNS 1,871,364

METHOD AND APPARATUS EUR MANUFACTURING RUBBER ARTICLES original Filed Maron 13. 1928 Patented Aug. 9, 1932 narran sears nausea WILLIS A. menons, or MoNTcL'AIR, New JERSEY, AssrGNoR "ro MORGAN s; wRrGVHT,

, on DnrRorr, iurcRIGAN; A coRPoRATroN or ivrrcnIGaN METHOD ann arrnR-Arus non ManurnoruR'rnG RUBBER yARTICLES Y Application sie@ Merch 1s, ieee, serial no. "261,196. :Renewed october' a2. i929.

rlhis invention relates to a method and apparatus for the manufacture of hollow rubber articles such as inner tubes for vehicle tires, but more particularly to theformation 5 of such articles directly from a rubber latex or otherV aqueous dispersion thereof bythe direct deposition of the rubber on a form or mandrel, and has for its primary object to provide a simple and effective method of pro- 10 ducing a superior article.

Further objects-are to provide a simple and durable form or mandrel construction on which the rubber may be uniformly deposited and which may be withdrawn fromV 15 the article after suoli article iscompletely formed ,to provide a method of making inner tubes as a complete annulus requiring no splicing or oining, to provide a hollow sectional form which will insure uniform de- 'ee positing of the rubber on the surface thereof,

25 the various sections of the form and locking the same in assembled position, to facilitate the removal of the formed article from the form or mandrel, and inV general to provide an improved means of manufacturing articles of rubber.

The many other objects and advantages of the invention will be better understood by reference to the following specication when considered in connection with the accompanying drawing illustrating` a selected embodiment thereof in which: Fig. 1 is a side elevation partially in section showing' a form or mandrel Iembodying the principles of the invention;

Fig. 2 is an enlarged longitudinal section of a portion of the form or mandrel shown in Fig. 1; and Y Fig. 3" is a similar sectionon the line 33 of Fig. 2.

Referrinfr to the drawing the mandrel orv form 5 comprises a hollow inner shell 6 and a filter covering 7. Theshell 6 is made of metal or other suitable shape-retaining material and comprises two sections 8 and 9 which are, adapted to engage to form acomplete annulus. The 'covering 7 maybe of any one of a number of dilf-erent-materials or ay combmation of such materials, audits primary vfunction is to act as a filter for the rubber latex ina manner which Vwill be presently described.

lll i ylhe section 9 fits between theendsof the section 8 and is adapted to be locked in posi"- tion therein by slidable bolts 10 which. are normally held retracted withinthe section 9 in .a disengaged position by springs 11. These bolts are actuated to lock the sections in assembled position by a cam l2 on a substantially U-shaped pipe 13 which eX- tends through a wall of the section 9 and is revoluble therein. rlhe'pipe 13 ends at its extremity against the wall opposite through which it enters the section 9. Y Bushings or vcollars 14 and 15 on this pipe coactwith the Wallsof the section to prevent axial move'- ment of the pipe while'permitting free rotation thereof. The bolts 10 are reciprocable throughthe end walls ofthesection 9 into I perfo-rations 16 in the opposing end walls ofthe section 8, as illustratedin the drawing, to perform their looking function. Ribs Y .Y

to stand ina vertical plane in usey but of course may occupy other positions. Ports 'derstood that the form shown is intended 24 may be provided in thel collar 14 and the" j V pipe13to section 9. The pipe 13 isconnected to a suitable source of vacuum or desired pressure (not shown) to provide a diiferential ofgpressure within provide forV adequate ldrainage of `and Without the form or mandrel 5 which permits the rubber to be more rapidly deposited on the filter. covering 7 as will be presently described. This pipe is adapted V bled form ormandrel during deposition.

The curved or side walls 25'and 26 of the sections 8 and 9 respectively are provided with a multiplicity of Vrelatively small and evenly distributed openings 27, only a small number being indicated inthe drawingin-i y A on the form'preferably with the vacuum still order to avoid confusioni* Preferablypthe end walls of. the section are not of sufficient thickness to provide an expanse of metal or impermeable material which might interfere with the proper deposit of the rubber at this point, but anylikelihood of this occur-l ring may be overcome by providing diagonal perfo-rations 28.. The spacing-.of the perforations. as 27 and: 28 may varyvv considerably,

but it is not advisable that this 'should be greater .than two inches 4and a less distance isi'preferable.v Openings `one-eighth of' an inch in diameter andspacedabout one inch are suitable.

The particular material composing the filter covering 7 forms `no part' of the present invention, and any suitable material or combination of materials may beused, which will permitl they passage of the` aqueousportion but not' the rubber of the latex or dispersion. AinA adyantageous form of' covering for the shell' 6 maybe provided by overlaying the sameyvithr wrappings of fibres, cords, fabric, vpaper or other permeable material andv then. applying tothis alcoveringof' filtering composition such as clayrslip. f A fabric strip may be applied to the joints between Vthe sections and lightly covered with the filtering. composition. Use of some reinforcing material throughout; the filtering composition is advantageous asit renders: the saine more durable andless liable to ble-fractured, butV is not essential. 'y

- The formiy or mandrel i illustrated in the drawing may be prepared for use by turning the pipe 'I3 sidewise to withdraw thebolts within the section 9 and then lowering this section from the position indicatedin dotY and dash lines'in Fig. l to the assembled position, as shownv in thatffigure, the lugs 17 acting' to guide this movement. Thepipe 13 is then turned to cause the cam 12 to force the bolts 10 into the corresponding perforations 1.6 in the section `8, thereby loeli-v filtering composition, it is placed in a body ofrubber latex or equivalent dispersionarfd the area within the sections of the form is eX- Apfter the form has' been ycoated with 'the I vThe fluid Yentering the form through the filtering material is sucked into the pipe 13 and carried away. The rubber is then dried on, and on the completion of ythe drying, vulcanized. To remove the form from the inner tube the pipe i3 is turned sideways to release the bolts lO. Air under pressure is then introduced int-o the form Athrough the pipel 18 and this `causes the coating of' rubber tobe ballooned away ,from the form. The Vsection Q-is nowpull-ed thro-'ugh the hole in the rubber l med `around vthepoint where the pipe 13 es into the seetion 9, after Whiclrthe sectien 8 is withdrawn in the same marmer, air under pressure being forced into' the rubber asinulus during this operation to facilitate the removal. Alternately or supplementarily a slit may be cut in the deposit of any delength to facilitate removal ofk the sections 8 and 9. Preferablythe slit, if made, will pass through the hole formed by the pipe Forlarger sizes of tubes, at least, it is deemed preferable to: use a slit and Where per# missible toV locate it in intersecting relation 1with the hole formed in the deposit by the pipe 13. i

The ost-.al valve base orpateh may their be appliedat the hole or slit which has been formed in the tube. lf the slit be located in the side wall or periphery of the tubeas it may, it may be closed by patching with rubber in any suitable and convenient manner. Prefera'bly butnot necessarily, a vulcanizable cement is employed in applying the Lvalve base and/ or applying a patch to close-the slit. The valve base may be applied to the `Jr'orm before the deposit'is made, or to the deposit beore it liasbeen dried". in such case, of course, it Woulldbo preferabfe to locate-'the slit for removal of the sections 8' and 9 at a point remote' from the valve base "and pre'ierablyin the outer 'feriphery of the tub Y The vulve stem may be applied and l to complete the tube for use in any mounted n suitable and convenient manner.

While as specifically disclosed, the inlet tubes providing pressure on the interior of the formed arti-cie or for evacuating the interior of the mandrel have been described as being applied only to the section 9', it is obvious that such pipes and connections might be applied to both sections 8 and 9 oir to section Sl alone with satisfactory results.

It will be readily evident that thecon struction and arrangement of parts may be very materially modied by o-ne skilled inthe art-without departing fromk the scope iio lli-5 of the invention and the particular embodiment herein shown and described was selected merely for the purpose of illustration. rEhe principles involved in this invention are applicable to the manufacture of practically any hollow rubber article. Theshape of the form and arrangement of the sections would naturally depend upon the particular article to be produced. y

Having thus described my invention, what l claim and desire to protect by Letters Patent is:

l. A form for themanufacture of hollow endless rubber articles by the deposition of rubber from an aqueous dispersion comprising a plurality of apertured sections adapted when assembled to constitute an endless sup-- port, a covering of filtering material on said sections capable of passing the aqueous portion butnot the rubber of the dispersion, at

least one of said sections carrying a conduit for the application of sources of fluid pressure to the interior of the sections.

2. A form for the manufacture of hollow7 i annular articles by the deposition of rubber from latex comprising a plurality of sections adapted when assembled to make an annulus, a stratum of material covering said sections capable of passing the aqueous portion but 1 not the rubber ofthe latex, and a conduit communicating with the interior of one of the sections.

3. A form for the manufacture of hollow annular articles by the deposition of rubber "1 from latex comprising a plurality of sections adapted when assembled to make an annulus, a stratum of materia-1 covering said sections capable of passing the aqueous portion but not the rubber of the latex, a conduit coinmunicating with the interior of one of the sec.- tions, and means for holding said sections in assembled relation and disengageable for removal from the article. y 4. A form for the manufacture of hollo annulararticles by the deposition of rubber from latex comprising a plurality of sections adapted when assembled to make an annulus,

a stratum of material covering said sections capable of passing the aqueousportion but net the rubber of the lateX, a conduit communicating with the interior of one ofthe sections and adapted to form a hole in the deposited article, and means for holding said section in assembled relation and disengageable for removal from the article, said conduit being rotatably mounted in the se-ction, and said means including spring actuated holding members, and a cam on said conduit for shifting the holding members against the operation of their springs.

5. A form for the manufacture of hollow annular articles by the deposition of rubber from latex comprising a plurality of sections adapted when assembled to make an annulus, a stratum of material covering said sections capable of passing the aqueous portion but, not vthe rubber of the latex, and a conduit'cominunicating with the interior of one of the sections, said sectionsgbeing proadapted when assembled to maire an annulus, t

a stratum of material covering said sections capable of passing the aqueous portion but not the rubberof the latex, a conduit coinvmunicating with theinterior of one of the sections, said sectionsbeingprovided with communicating passages, and ymeans.Y for drainingithe interior of the sections.

'7. A form for the manufacture of hollow .annular articles by the deposition of rubber from lateirc'omprising a plurality of sections adapted when assembled to make an annulus, a stratum of material covering said sections lcapable of passing the aqueous portion but not the rubber of the latex, a conduit communicating with the interior of one of the'y sections, said sections being provided with communicating passages, and means for draining the interior ofthe sections, said last named means including a pipe; provided with an intake opening at substantially the lowermost point in the interior of the asl sembled sections.

8. .Aform yfor the manufacture of inner tubes by the deposition of rubber. from an aqueous dispersion thereof, which consists ofV a plurality of engageable sections, means for disengageably securing the Ysections in annular arrangement, means for supporting the a'nnulus in a rubber dispersion so as to form ahole in the article at one point, and means of communication with the interior of the form through .the supporting means.

9; A11 internal annular form for the manufacture of inner tubes'by the deposition of rubber from an aqueous dispersion thereof, which consists of two sections one of which is relatively short, means for disengageably securing the sections into anV annulus, means for supporting the annulus in a rubber. dissb l persion so as to form a hole in the article beingdeposited at only one point, and means connected withjthe supporting means: for communication with the interior of the-form.

l0. That method of' manufacturing rubber endless tubes which comprises effecting thev deposition of the' solid constituents of latex upon the exterior surface of a continuous circular form giving mandrel,forming in the tube an aperture substantially smaller than a cross section of the mandrel, vulcanizing the rubber tube, and withdrawing the mandrel through the aperture formed in the tube.

1l. That method of manufacturing rubber endless tubes which comprises-effecting the deposition of the solid constituents of latex upon the exterior surface of a continuous tube an aperture ofarea substantiallysmaller Y circular formgiving mandrel, forming in: the

than the area of any cross-section ofthe mandrel, vulcanizing'the rubber-at least to a degree sutlicient to prevent rupture 'of the tube upon -withdrawal of the Vmandrel through the aperture, and withdrawing the Vmandrel through the aperture.

l2. That method of manufacturing rubber inner tubes which comprises effecting the deposition of the solid constituentsfof latex upon the exterior surface of' a` continuous circular form givingmandrel, forming in the rubber tube an aper-tureofa size approximating the size of a valv-estem, vulcanizin-g the rubber at least to a degree sufficient to prevent i rupture of the tube uponwithdrawal of the mandrel therefrom vthrough the aperture,

withdrawing the mandrel through the aperture from the tube, and iinishing the tube.

13. That method of manufacturing rubber inner tubes which comprises effecting the deposition of the solid constituents Y of latex yupon the exterior surface of a continuous circular form giving mandrel having a projectionadapted to form during deposition an aperture in the tube of a size to accommodate a valve stem, effecting. the vulcanizatlon of the rubber tube, withdrawing .the mandrel through the aperture from the tube, and

finishing the tube. Y

` 14. That method of manufacturing endless tubes which comprises effecting the deposition of the solid constituents Vof latex Vupon the exterior surface of a continuous circular form giving mandrel, forming in the tube an aperture substantially smaller than across section of the-mandrel, vulcanizing the rubber tube, opening the mandrel, and withdrawing the mandrel through the'aperture formed in the tube. I Y' 15. That method of manufacturing rubber endless tubes whichl comprises eecting the deposition'of the solid constituents of latex upon the exterior surface of aV continuous circular form giving mandrel, forming in the tube an aperture substantially-'smaller than the cross section of a mandrel, opening the mandrel, and withdrawing the mandrel through the aperture `formed in the tube.

'Signed at New York, N. Y.,'this 12th day of March, 1928. Y

- e WILLIS A. GIBBONS.

'Larmes 

